This application claims the priority benefit of Taiwan application serial no. 102135524, filed on Oct. 1, 2013. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
1. Field of the Invention
The invention relates to a display device, and more particularly, to a stereo display device.
2. Description of Related Art
In recent years, continuous advancement of display technologies results in increasing demands on display quality of display devices, such as image resolution, color saturation, and so on. To satisfy users' requirements for viewing true images, display devices that are not only characterized by high image resolution and satisfactory color saturation but also capable of displaying stereo images have been developed.
Among the existing stereo display technologies, the spatial-multiplexed technology has flourished and matured. According to the spatial-multiplexed technology, in order to create stereo effects, different spatial viewing zones may be generated by means of parallax barrier or lenticular lenses, such that right and left eyes of a user may respectively receive different image information. The manufacturing technique of applying the parallax barrier is more mature than the manufacturing technique of employing the lenses and thus has been extensively used.
In the conventional stereo display device formed by means of the parallax barrier, the unfavorable alignment precision of assembling machines may lead to rotation errors and motion differences when a display panel and a barrier panel are aligned and adhered to each other. Hence, how to resolve the issue of alignment errors and accordingly reduce light leakage, color shift, and noise for improving the display quality of the stereo display device has drawn attention from the industry.
The invention is directed to a stereo display device capable of reducing rotation errors and increasing tolerance of alignment errors without sacrificing the display quality.
In an embodiment of the invention, a stereo display device that includes a display panel and a barrier panel is provided. The display panel includes a plurality of sub-pixel units arranged in an array along an X-direction and a Y-direction and at least three sub-pixel units form a pixel unit. The barrier panel is located at one side of the display panel and includes a plurality of first electrodes, a plurality of second electrodes, and an optically anisotropic medium. An included angle between an extension direction of the first electrodes and the Y-direction is +θ1, and θ1≠0 degree. An included angle between an extension direction of the second electrodes and the Y-direction is −θ2, and θ2≠0 degree. The optically anisotropic medium is located between the first electrodes and the second electrodes.
In an embodiment of the invention, another stereo display device that includes a display panel and a barrier panel is provided. The display panel has an edge and includes a plurality of sub-pixel units arranged in an array along an X-direction and a Y-direction and at least three sub-pixel units form a pixel unit. The barrier panel is located at one side of the display panel and has an edge. Here, an included angle between the edge of the display panel and the edge of the barrier panel has a rotation threshold of alignment error, and the rotation threshold of alignment error is 2θ A resolution of the display panel is A×C, A<C, and 2θ satisfies:
Here, P represents a width of one pixel unit, and D represents an alignment error threshold between the display panel and the barrier panel.
In an embodiment of the invention, yet another stereo display device that includes a display panel and a barrier panel is provided. The display panel is shaped as a rectangle and has a first side. Besides, the display panel includes a plurality of sub-pixel units arranged in an array along an X-direction and a Y-direction. The barrier panel is located at one side of the display panel. Besides, the barrier panel is shaped as a rectangle and has a second side. An acute angle between the first side and the second side ranges from 0.01 degree to 0.1 degree. The barrier panel includes a plurality of first electrodes extending along the Y-direction.
In view of the above, electrodes rotating in different directions are respectively arranged on two substrates of the barrier panel; after the display panel and the barrier panel are adhered to each other, the electrodes deviated from the Y-direction (i.e., the central line) to the less extent may serve as the barrier electrodes, and the electrodes deviated from the Y-direction to the greater extent may serve as the common electrodes (Com). Thereby, the rotation errors may be reduced, and the tolerance of the alignment errors may be doubled, so as to comply with the manufacturing requirements. Moreover, the stereo display device described herein is applicable to products with the large pixel per inch (PPI) or the small single barrier pitch (SBP).
Several exemplary embodiments accompanied with figures are described in detail below to further describe the invention in details.
The accompanying drawings are included to provide further understanding, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments and, together with the description, serve to explain the principles of the invention.
With reference to
Here, the display panel 110 includes a pair of substrates 120 and 130, a pixel array 122 located on the substrate 120, and a display medium 140 located between the pair of substrates 120 and 130. Besides, the display panel 110 may be any component capable of displaying images, such as a liquid crystal display (LCD) panel, and organic light-emitting diode (OLED) display panel, an electrophoretic display panel, a plasma display panel, or any other display panel.
According to the present embodiment, a color of each column of the sub-pixel units S is repeated in a red-green-blue order, and a color of each row of the sub-pixel units S is identical. For instance, in the display panel 110 shown in
If the display panel 110 is an LCD panel, the display medium 140 is liquid crystal molecules, for instance. In other exemplary embodiments, if the display panel 110 is an OLED display, the display medium 140 is an organic light-emitting layer, for instance; if the display panel 110 is an electrophoretic display panel, the display medium 140 is an electrophoretic display medium, for instance; if the display panel 110 is a plasma display panel, the display medium 140 is a plasma display medium, for instance. Besides, in the display panel 110, if a non-self-illuminating material (e.g., a liquid crystal material) is applied as the display medium 140, the stereo display device 100 may selectively include a light source module for providing the light source required for displaying images.
With reference to
The first substrate 160 and the second substrate 170 are opposite to each other and may be made of glass, quartz, organic polymer, or any other appropriate materials.
The optically anisotropic medium 180 is located between the first substrate 160 and the second substrate 170. Here, the optically anisotropic medium 180 is characterized by birefringence, e.g., liquid crystal molecules or other appropriate substances. The liquid crystal molecule, for instance, often has a first-axis refractive index (no) and a second-axis refractive index (ne). The first-axis refractive index (no) and the second-axis refractive index (ne) are normally referred to as the short-axis refractive index and the long-axis refractive index of the liquid crystal molecules. The optically anisotropic medium 180 is arranged according to the distribution of the electric field in the barrier panel 150.
The first electrode layer 162 and the second electrode layer 172 are respectively located at an inner side of the first substrate 160 and at an inner side of the second substrate 170, and the inner sides of the first and second substrate 160 and 170 adjoin the optically anisotropic medium 180. In other words, the optically anisotropic medium 180 is located between the first electrode layer 162 and the second electrode layer 172.
To be specific, in the present embodiment, the first electrode layer 162 includes a plurality of first electrodes 164. The first electrodes 164 are bar-shaped electrodes arranged in parallel, for instance, which should however not be construed as a limitation to the invention. In other embodiments, the first electrodes 164 may also be other appropriate patterned electrodes. An included angle between an extension direction of the first electrodes 164 and the Y-direction is +θ1, and θ1≠0 degree. In addition, the second electrode layer 172 includes a plurality of second electrodes 174. The second electrodes 174 are bar-shaped electrodes arranged in parallel, for instance, which should however not be construed as a limitation to the invention. In other embodiments, the second electrodes 174 may also be other appropriate patterned electrodes. An included angle between an extension direction of the second electrodes 174 and the Y-direction is −θ2, and θ2≠0 degree. In the present embodiment, |θ1−θ2|≦θ, or θ1=θ2. If the included angle is +θ, it means that the included angle is levorotary; if the included angle is −θ, it means that the included angle is dextrorotary. The first electrodes 164 and the second electrodes 174 may be made of a transparent conductive material that includes metal oxide, e.g., indium tin oxide, indium zinc oxide, aluminum tin oxide, aluminum zinc oxide, indium germanium zinc oxide, other appropriate oxide, or a stacked layer containing at least two of the above.
In the present embodiment, the stereo display device 100 further includes an adhesive layer (not shown) for adhering the display panel 110 and the barrier panel 150, for instance. Thereby, after the display panel 110 and the barrier panel 150 are adhered to each other, the barrier panel 150 ensures that the left eye of a user merely observes the pixels in the left-eye image, and that the right eye of the user merely observes the pixels in the right-eye image, so as to achieve the stereo effects. The stereo display device 100 may further include a polarizer (not shown) located on both a surface of the display panel 110 and a surface of the barrier panel 150, for instance.
To clearly illustrate the relationship between the display panel 110 and the barrier panel 150,
Here, P represents a width of one pixel unit U, D represents an alignment error threshold between the display panel 110 and the barrier panel 150, and 0.005 degree≦θ≦0.05 degree. For instance, it is assumed that A is 720, C is 1280, and P is 77.1 μm. Under said circumstances, if D is 5 μm, then θ is 0.0052 degree; if D is 50 μm, then θ is 0.052 degree.
In particular, the display panel 110 has a rectangular shape and a first side 110a. The barrier panel 150 has a rectangular shape and a second side 150a. An acute angle 20 between the first side 110a and the second side 150a ranges from 0.01 degree to 0.1 degree. That is, due to the unfavorable alignment precision of assembling the machines, the acute angle is often formed between the first side 110a of the display panel 110 and the second side 150a of the barrier panel 150, the acute angle resulting from the alignment error has the maximum value 2θ, and 0.005 degree≦θ≦0.05 degree. As a matter of fact, the value of 2θ may vary if the alignment precision of assembling the machines varies.
To clearly illustrate the relationship between the sub-pixel units S in the display panel 110 and the electrodes in the barrier panel 150,
With reference to
In the present embodiment, after the display panel 110 and the barrier panel 150 are adhered to each other, first electrodes 164 serve as the barrier electrodes and the second electrodes 174 serve as the common electrodes (Corn) if θ1<θ2. Particularly, in the present embodiment, the sides 164a of the first electrodes 164 may extend along the Y-direction and are parallel to the sides Sa of the sub-pixel units S (i.e., the first electrodes are not deviated from the Y-direction), the first electrodes 164 may serve as the barrier electrodes, and the second electrodes 174 may serve as the common electrodes. Due to the alignment errors, the barrier electrodes may be shifted and cannot completely block the underlying sub-pixel units S, thus resulting in the issues of light leakage, color shift, and noise. However, in the present embodiment, the bar-shaped barrier electrodes may be accurately aligned to the sub-pixel units S in each column, the shift of the barrier electrodes caused by the alignment errors may be prevented, and said issues of light leakage, color shift, and noise may be resolved.
As shown in
With reference to
As provided above, there is an included angle between the extension direction of the first electrodes 164 and the Y-direction, and there is also an included angle between the extension direction of the second electrodes 174 and the Y-direction. Besides, each of said included angles is half the rotation threshold of alignment error (i.e., 20) between the display panel 110 and the barrier panel 150. Hence, the resultant alignment precision is satisfactory no matter whether the display panel 110 and the barrier panel 150 are accurately aligned and adhered to each other. That is, the alignment precision described herein is less than or equal to θ, and 0.005 degree≦θ≦0.05 degree.
In the previous embodiments shown in
With reference to
When the first electrodes 264 serve as the barrier electrodes, and the second electrodes 274 serve as the common electrodes, a barrier potential V1 is applied to the first barrier electrodes 266; at the same time, a common potential (constant potential) Vcom is applied to the first common electrodes 268, the second common electrodes 278, and the second barrier electrodes 276. Here, the barrier potential V1 is higher or lower than the common potential Vcom so as to generate a potential difference. Similarly, when the second electrodes 274 serve as the barrier electrodes, and the first electrodes 264 serve as the common electrodes, a barrier potential V1 is applied to the second barrier electrodes 276; at the same time, a common potential Vcom is applied to the second common electrodes 278, the first common electrodes 268, and the first barrier electrodes 266. Here, the barrier potential V1 is higher or lower than the common potential Vcom so as to generate a potential difference. According to the present embodiment, the first barrier electrodes 266 are located between the first common electrodes 268 and the optically anisotropic medium 180, and the second barrier electrodes 276 are located between the second common electrodes 278 and the optically anisotropic medium 180; however, the invention is not limited thereto. Based on actual demands, the first common electrodes 268 may be located between the first barrier electrodes 266 and the optically anisotropic medium 180, and the second common electrodes 278 may be located between the second barrier electrodes 276 and the optically anisotropic medium 180.
Since the first common electrodes 268 and the first barrier electrodes 266 are alternately arranged, and the second common electrodes 278 and the second barrier electrodes 276 are alternately arranged, the common electrodes and the barrier electrodes belonging to different film layers may be spatially overlapped. Thereby, the common electrodes and the barrier electrodes may be closely arranged, so as to prevent light leakage and color shift and achieve favorable stereo display effects.
In the embodiment depicted in
With reference to
To sum up, in the stereo display device provided herein, the included angle between the extension direction of the first electrodes and the Y-direction is +θ1, and the included angle between the extension direction of the second electrodes and the Y-direction is −θ2, and each of the included angles is half the rotation threshold of alignment error (2θ). That is, the electrodes rotating in different directions are respectively arranged on the two substrates of the barrier panel; after the display panel and the barrier panel are adhered to each other, the electrodes deviated from the Y-direction (i.e., the central line) to the less extent may serve as the barrier electrodes, and the electrodes deviated from the Y-direction to the greater extent may serve as the common electrodes. Thereby, the rotation errors may be reduced, and the tolerance of the alignment errors may be doubled, so as to comply with the manufacturing requirements. Moreover, the stereo display device described herein is applicable to products with the large PPI or the SBP. Namely, according to the design of the electrodes in the barrier panel provided herein, the alignment of the extension direction of the barrier electrodes to the central line is precise, and said alignment precision is raised to a level smaller than or equal to half the alignment precision 20 of adhering the machines.
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.
Number | Date | Country | Kind |
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102135524 | Oct 2013 | TW | national |